U.S. patent number 7,528,404 [Application Number 10/555,291] was granted by the patent office on 2009-05-05 for assembly of a semiconductor die attached to substrate with oxazoline derivative bearing an electron donor or acceptor functionality.
This patent grant is currently assigned to Henkel AG & Co. KGaA. Invention is credited to Osama M. Musa, Ruzhi Zhang.
United States Patent |
7,528,404 |
Musa , et al. |
May 5, 2009 |
Assembly of a semiconductor die attached to substrate with
oxazoline derivative bearing an electron donor or acceptor
functionality
Abstract
An assembly of a semiconductor die attached to a substrate is
made with a composition comprising compounds that contain an
oxazoline functionality and an electron acceptor or an electron
donor functionality. Electron donor functionalities include
styrenic, cinnamyl, and vinyl ether groups. Electron acceptor
functionalities include maleimide, acrylate, fumarate, and maleate
groups. An exemplary compound has the structure: formula (I).
##STR00001##
Inventors: |
Musa; Osama M. (Hillsborough,
NJ), Zhang; Ruzhi (Pennington, NJ) |
Assignee: |
Henkel AG & Co. KGaA
(Dusseldorf, DE)
|
Family
ID: |
34912882 |
Appl.
No.: |
10/555,291 |
Filed: |
February 17, 2004 |
PCT
Filed: |
February 17, 2004 |
PCT No.: |
PCT/US2004/004736 |
371(c)(1),(2),(4) Date: |
November 02, 2005 |
PCT
Pub. No.: |
WO2005/083771 |
PCT
Pub. Date: |
September 09, 2005 |
Prior Publication Data
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|
|
Document
Identifier |
Publication Date |
|
US 20060263928 A1 |
Nov 23, 2006 |
|
Current U.S.
Class: |
257/40 |
Current CPC
Class: |
C07D
263/10 (20130101); C07D 263/14 (20130101); C07D
413/12 (20130101); C08G 61/00 (20130101); C08G
61/02 (20130101); C08G 73/02 (20130101); H01L
21/563 (20130101); H01L 23/293 (20130101); H01L
24/29 (20130101); H01L 24/83 (20130101); H01L
2224/73203 (20130101); H01L 2224/8385 (20130101); H01L
2924/01005 (20130101); H01L 2924/01011 (20130101); H01L
2924/01013 (20130101); H01L 2924/01015 (20130101); H01L
2924/0102 (20130101); H01L 2924/01029 (20130101); H01L
2924/01046 (20130101); H01L 2924/01047 (20130101); H01L
2924/0105 (20130101); H01L 2924/01056 (20130101); H01L
2924/01078 (20130101); H01L 2924/01079 (20130101); H01L
2924/01082 (20130101); H01L 2924/07802 (20130101); H01L
2224/29 (20130101); H01L 2224/2919 (20130101); H01L
2924/01006 (20130101); H01L 2924/014 (20130101); H01L
2924/0665 (20130101); H01L 2224/29101 (20130101); H01L
2924/0665 (20130101); H01L 2924/00 (20130101); H01L
2224/29101 (20130101); H01L 2924/014 (20130101); H01L
2924/00 (20130101); H01L 2924/00013 (20130101); H01L
2224/29199 (20130101); H01L 2924/00013 (20130101); H01L
2224/29299 (20130101); H01L 2924/00013 (20130101); H01L
2224/2929 (20130101); H01L 2224/29324 (20130101); H01L
2224/2929 (20130101); H01L 2224/29339 (20130101); H01L
2224/29344 (20130101); H01L 2224/29347 (20130101); H01L
2224/29355 (20130101); H01L 2224/29364 (20130101); H01L
2224/29369 (20130101); H01L 2224/29386 (20130101); H01L
2224/29388 (20130101); H01L 2224/29393 (20130101); H01L
2224/29393 (20130101); H01L 2924/00014 (20130101); H01L
2224/29344 (20130101); H01L 2924/00014 (20130101); H01L
2224/29339 (20130101); H01L 2924/00014 (20130101); H01L
2224/29347 (20130101); H01L 2924/00014 (20130101); H01L
2224/29369 (20130101); H01L 2924/00014 (20130101); H01L
2224/29364 (20130101); H01L 2924/00014 (20130101); H01L
2224/29355 (20130101); H01L 2924/00014 (20130101); H01L
2224/29324 (20130101); H01L 2924/00014 (20130101); H01L
2224/29386 (20130101); H01L 2924/04642 (20130101); H01L
2924/00014 (20130101); H01L 2224/29386 (20130101); H01L
2924/0503 (20130101); H01L 2924/00014 (20130101); H01L
2224/29386 (20130101); H01L 2924/05432 (20130101); H01L
2924/00014 (20130101); H01L 2224/29388 (20130101); H01L
2924/00014 (20130101); H01L 2224/2929 (20130101); H01L
2924/0665 (20130101); H01L 2924/00014 (20130101); H01L
2924/00013 (20130101); H01L 2924/00013 (20130101); H01L
2224/29099 (20130101); H01L 2924/10253 (20130101); H01L
2924/10253 (20130101); H01L 2924/00 (20130101) |
Current International
Class: |
H01L
29/08 (20060101); H01L 35/24 (20060101); H01L
51/00 (20060101) |
Field of
Search: |
;257/40 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Nakahama, Sejichi et al.: "Anionic Living Polymerization of
Styrenes Containing Electron-withdrawing Groups"; Makromol. Chem.,
Macromol. Symp. 67, 223-236 (1993). cited by other.
|
Primary Examiner: Jackson; Jerome
Assistant Examiner: Ho; Anthony
Attorney, Agent or Firm: Gennaro; Jane E.
Claims
What is claimed is:
1. An assembly of a semiconductor die attached to a substrate with
a composition consisting essentially of a compound having the
structure, ##STR00009## a curing agent and a filler.
Description
FIELD OF THE INVENTION
This invention relates to an assembly of a semiconductor die
attached to a substrate with a curable or cured composition that
contains a compound having both oxazoline functionality and
electron acceptor or electron donor functionality.
BACKGROUND OF THE INVENTION
The fabrication of semiconductor packages and microelectronic
devices call for the use of adhesive and encapsulant compositions
in assembly processes. Typical compositions include radical-curable
compositions and electron donor/electron acceptor systems. These do
not always give optimum performance in certain uses and there is
still a need for performance materials within the semiconductor
fabrication industry.
SUMMARY OF THE INVENTION
This invention is directed to an assembly of a semiconductor die
attached to or supported on a substrate with a composition
comprising a compound that contains an oxazoline functionality and
an electron acceptor or an electron donor functionality. The
composition is applied in a curable state and cured in situ.
Electron donor functionalities include styrenic, cinnamyl, and
vinyl ether groups. Electron acceptor functionalities include
maleimide, acrylate, fumarate, and maleate groups.
DETAILED DESCRIPTION OF THE INVENTION
Oxazolines are five-membered heterocyclic compounds having a
nitrogen atom, an oxygen atom, and one double bond. The double bond
may be located in one of the three positions, making possible the
existence of three different oxazoline rings: 2-oxazolines (most
common), 3-oxazolines, and 4-oxazolines. Oxazolines undergo
cationic ring opening homopolymerization; electron donor/electron
acceptor systems undergo free radical polymerization. Thus,
compounds having at least one oxazoline group and one electron
donor or electron acceptor functionality per molecule have the
capability of undergoing dual cure, both thermal and radiation.
The compositions used herein comprise a compound having oxazoline
and electron donor or electron acceptor functionalities, curing
agent and filler. In those compositions in which an electron
acceptor functionality is present, the curing agent is optional.
The composition can be a paste, prepared by blending or milling, or
can be a film, prepared by standard film making techniques known to
those skilled in the art.
The composition will consist mainly of the compound having
oxazoline and electron donor or electron acceptor functionalities;
alternatively, the compound having oxazoline and electron donor or
electron acceptor functonalities can be used in a lesser amount as
an adhesion promoter to one or more other curable resins. When used
as an adhesion promoter, the amount used in the composition will be
an effective amount and will range from 0.005 to 20.0 percent by
weight of the formulation.
When used as an adhesion promoter, the main component will be any
other suitable curable resin, including, for example, epoxy, vinyl
ether, thiolene, a resin derived from cinnamyl and styrenic
starting compounds, fumarate, maleate, acrylate, maleimide, cyanate
ester, oxetane, phenol, amino resin, propargyl ether,
benzocyclobutene, and benzoxazine.
Suitable curing agents are thermal initiators and photoinitiators
present in an effective amount to cure the composition. In general,
those amounts will range from 0.1% to 30%, preferably 1% to 20%, by
weight of the total organic material (that is, excluding any
inorganic fillers) in the composition.
Preferred radical initiators include peroxides, such as butyl
peroctoates and dicumyl peroxide, and azo compounds, such as
2,2'-azobis(2-methyl-propanenitrile) and
2,2'-azobis(2-methyl-butanenitrile). Preferred cabonic initiators
include iodonium, oxonium, sulfonium, sulfoxonium, and various
other onium salts. Other suitable cationic initiators include Lewis
acid catalysts and alkylation agents, such as, arlysulfonate
esters, e.g., methyl-p-toluenesuffonate and methyl
trifluoromethanesulfonate. A preferred series of photoinitiators
are those sold under the trademark Irgacure or Rhodorsil 2074 by
Ciba Specialty Chemicals. In some formulations, both thermal
initiation and photoinitiation may be desirable: the curing process
can be started either by irradiation, followed by heat, or can be
started by heat, followed by irradiation.
The curable compositions will cure within a temperature range of
60.degree. C. to 250.degree. C., and curing will be effected within
a range of three seconds to three hours. The actual cure profile
will vary with the components and can be determined without undue
experimentation by the practitioner.
Suitable fillers can be conductive or nonconductive. Exemplary
conductive fillers are carbon black, graphite, gold, silver,
copper, platinum, palladium, nickel, aluminum, silicon carbide,
boron nitride, diamond, and alumina. Exemplary nonconductive
fillers are particles of vermiculite, mica, wollastonite, calcium
carbonate, titania, sand, glass, fused silica, fumed silica, barium
sulfate, and halogenated ethylene polymers, such as
tetrafluoroethylene, trifluoro-ethylene, vinylidene fluoride, vinyl
fluoride, vinylidene chloride, and vinyl chloride. Fillers
generally will be present in amounts of 20% to 90% by weight of the
formulation.
These compositions are useful for attaching semiconductor dies to
substrates or for supporting a semiconductor die as an underfill
between the die and substrate. Typical substrates are fabricated
from metal, for example, copper, silver, gold, nickel, alloys (such
as, 42Fe/58Ni alloy), silver-coated copper, or palladium-coated
copper; from organic material, for example, polyimides, polyamides,
or polyesters; from ceramic; and from composites or laminates (such
as, printed wire boards).
In a typical die attach operation, the adhesive in paste or film
form is placed onto the substrate, such as the center paddle of the
leadframe, and the silicon die contacted to the adhesive with heat
and pressure. The exact process and processing parameters may vary
from operation to operation. These parameters and processes are
known to those skilled in the art and are not meant to form a part
of this invention.
In a typical underfill operation, connections are made between
electrical terminals on the die and corresponding electrical
terminals on the substrate using metallic or polymeric solder. A
bump of solder is placed on the terminals of the substrate, the
terminals are aligned and contacted, and the resulting assembly
heated to reflow the solder. A gap is created between the die and
the substrate, which is filled with a polymeric encapsulant or
underfill to reinforce the interconnect. There are variations in
the processes for the underfill, for example, the underfill
encapsulation may take place after the reflow of the solder or
simultaneously with the reflow of the solder. These processes are
known to those skilled in the art and are not meant to form a part
of this invention.
The gist of this invention is the use of the oxazoline compounds as
a die attach or underfill encapsulant for attaching or suppporting
semiconductor dies to substrates.
Various synthetic routes to the oxazoline compounds can be devised
with reference to the following synthetic schemes. To prepare a
compound having both styrenic and oxazoline functionality such
as
##STR00002## a procedure according to A. Zerroukhi, A. Ainser, A.
Arsac, N. Mignard, and B. Marculescu, Polymer Bulletin, 42, 535,
1999, is used. Initially, vinylbenzyl chloride is reacted with
sodium cyanide to give vinylbenzyl cyanide, which is then reacted
with ethanolamine to give the vinylbenzyloxazoline.
To prepare a compound having both maleimide and oxazoline
functionality such as
##STR00003## maleic anhydride (in acetonitrile) is reacted with
6-aminocaprioc acid (in acetic acid) to form the amic acid adduct.
The adduct is dehydrated to close the ring and form the maleimide.
Procedures for this reaction are known in the art. The product,
6-maleimidocaproic acid, is then reacted with
2-(3-hydroxy-2-propyl) -2-oxazoline (in toluene heated to
80.degree. C.) with a catalytic amount of sulfuric acid, worked up,
and the product isolated.
To prepare a compound having both cinnamyl and oxazoline
functionality such as
##STR00004## 2-(3-hydroxy-2-propyl)-2-oxazoline in an excess amount
of 50% NaOH and a catalytic amount of tetrabutyl ammonium hydrogen
sulfate is reacted with cinnamyl chloride in toluene for several
hours first at 53.degree. C., then at 75.degree. C. The reaction is
allowed to cool to room temperature and the organic layer extracted
and washed with brine three times. The isolated organic layer is
dried over MgSO.sub.4, filtered and the solvent removed in vacuo to
give the product.
To prepare a compound having both styrenic and oxazoline
functionality such as
##STR00005## 3-isopropenyl-.alpha.,.alpha.-dimethylbenzyl
isocyanate (m-TMI) and 2-(3-hydroxy-2-propyl)-2-oxazoline are
solvated in toluene and reacted under nitrogen with a catalytic
amount of dibutyltin dilaurate at 60.degree. C. for several hours.
After the reaction is allowed to cool to room temperature, the
solvent is removed in vacuo to give the product.
To prepare a compound having both acrylate and oxazoline
functionality such as
##STR00006## 2-(3-hydroxy-2-propyl)-2-oxazoline and triethylamine
are mixed in dry methylene chloride at 0.degree. C. The appropriate
equivalent of acryloyl chloride dissolved in dry methylene chloride
is carefully added and the mixture allowed to react for several
hours. The solvent is evaporated and the crude product is purified
by column chromatography using a gradient of hexane/ethyl
acetate.
To prepare a compound having both vinyl ether and oxazoline
functionality such as
##STR00007## 2-(3-hydroxy-2-propyl)-2-oxazoline in an excess amount
of 50% NaOH and a catalytic amount of tetrabutyl ammonium hydrogen
sulfate is reacted with 2-chloroethyl vinyl ether in toluene for
several hours, first at 53.degree. C., then at 75.degree. C. The
reaction is allowed to cool to room temperature and the organic
layer extracted and washed with brine three times. The isolated
organic layer is dried over MgSO.sub.4, filtered, and the solvent
removed in vacuo to give the product.
To prepare a compound having both maleate and oxazoline
functionality such as
##STR00008## 2-isopropenyl-2-oxazoline and 2-mercaptoethanol are
reacted in toluene at 70.degree. C. A solution of
azodiisobutyronitrile (AIBN) in toluene is added to the mixture,
and the reaction continued at 70.degree. C. for several hours. The
2-isopropenyl-2-oxazoline/2-mercaptoethanol adduct is obtained
after removal of the solvent under reduced pressure. This
2-isopropenyl-2-oxazoline/2-mercaptoethanol adduct is then reacted
under nitrogen with maleic anhydride in 300 mL of dimethoxyethane
at 70.degree. C. for one hour. After cooling, the contents of the
reaction are poured into heptane. The resulting product is dried at
40.degree. C. in vacuo for 24 hours.
* * * * *